Electric toothbrush



April 9, 1940. T. l. MOSELEY 2,196,661

ELECTRIC Too'ranus Filed nec. 13, 1937 *ZIZ T1' E4' l 27- v 27 l 33 /9 25 32 INVENroR. 3 l. M 'OML/Nso/VJ/fosnfr /2 ATTORNEY Patented Apr. l9, 194i) assess-I ELECTRIC TOOTHBBUSH I. Moseley, San Francisco, Calif., assignor to Motodent Ine., Los Angeles, Calif., a omiten of California application December 1s, 1937, serial No. 119,427

iClalma.

I in appearance, simple and compact in construction and may be safely employed to emciently cleanse teeth in the human mouth.

In actual practice I employ an electrical vibratory motor which is entirely enclosed within a moisture-prooi casing of molded dielectric material of pleasing external design, and of a shape that it may be readily grasped in the hand of the user. Detachably connected with this casing is a projecting arm carrying an oscillatory brushing element so mechanically connected with the motor that operation oi the latter will rapidly oscillate the brushing element. This brushing element is readily replaceable so that it may be replaced as desired. i

One form which the invention may assume is exemplified in the following description and illustrated by way oi' example in the accompanying drawing, in which:

Fig. 1 is a perspectiveview of my improved toothbrush with one-haii' of the casing removed showing the internal construction thereof.

Fig. 2 is a plan view of the toothbrush with onehalf oi the casing removed and with the brush arm in longitudinal section.

. Fig. 3 is a longitudinal sectional view taken on line III- III oi' Fig. 2.

111g. 4 is a transverse sectional view taken on line IV-IV of Fig. 3.

Flg. 5 is a perspective view of the brush arm.

Referring more particularly to the accompanying drawing. I0 indicates a toothbrush including a hollow casing II of dimensions and configuration that it may comfortably be grasped in the hand of the user. The casing II is centrally and longitudinally divided into two halves which are.

counter parts and which are secured together by screws or other suitable means. when joining the halves. moisture-prooi sealing material ls applied to their abutting faces to insure that the casing will be moisture-prooi. The casing II is preferably molded of Bakelite or other material having similar advantageous characteristics.

Disposed within the casing and secured therein is an electrical vibratory motor I2, the field winding Il of which is firmly fastened Inoue-half of the casing as illustrated in Fig. 2. Y The current conductors I 5 for the motor are led in through one (ci. ls-zs) end of the casing in a moisture-proof manner as illustrated. For this purpose a bushing I 5a of dielectric material is sealed in an end' aperturez Iib in the casing.

Projecting from the end of the casing II, opposite that in which the current conductors i5 are led, is a hollow metallic i'errule I6 which is square in cross section and having a square opening extending longitudinally therethrough. The inner end of this ferrule I6 nests in a square opening molded in the ends of the two casing halves as illustrated. 'I'he inner end of the ferrule IB is provided with a circumscribing ilange Il iltting a groove in the casing halves II so as to iirmly hold the ferrule I6 against endwise movement.

Reciprocably mounted in the ferrule I6 is a rack I8 likewise squarein cross section and snugly, although slidably, fitting the square bore through the ferrule I6. The inner end of the rack Il projects into the casing II and is secured to the armature I9 oi the motor I2. The armature I! is spring balanced by springs 20 for obvious reasons. The outex` endo-f the ck I8 projects from w the outer end oi the ierrule I6 and is formed with rack teeth 2l 4on one side. A brush arm 22 is provided which is formed with a square longitudinal bore 23 slidably fitting over the ferrule I6 so that its inner end will abut against the adjacent end of the casing II. As will be obvious to those skilled in the art, suitable interrupting means, not shown, may be operated by the reciprocating parts to break the iield circuit periodically and adapt the device to a current supply of the customary domestic type.

The bore oi the ferrule is formed with a keyway 23a adapted to receive a protuberance or key 24 xed on one side of the ferrule Ii so that the brush arm 22 can only properly ilt on the ierrule in one position.

'Ihe outer end of the brush arm 22 is formed with a circular hollow socket 25, the center of which is perpendicular to the bore 23 and slightly spaced from one side thereof so that the bore 23 extends substantially tangentially from the socket 25. 'Ihe toothed end 2I of the rack Il extends tangentially into the socket 25 to mesh with a pinion 2l formed on a disk-like bristle holder 21 which is rotatably mounted in the socket concentrically thereof. It will be seen that at the outer end oi the socket is an annular ilange 21a within which the disk-like bristle holder 21 is journalled.

The pinion 26 abuts against the inner end of the socket and the inner face of the disk-like bristle holder 2l abuts against the outer end o! the socket. A pintle 2l is provided which is seon the bristle holder 21, that the fastener 29 will the button 32.

4Q associated with a movable switch arm 3| of aV cured at its inner end in the inner end of the socket and projects outwardly to rotatably receive the bristle holder 21, and acts as a shaft therefor. A snap fastener 25 is secured in the bristle holder 21 which snaps over the outer end of the pintle 28 to hold -the bristle holder in its proper position relative to the socket 25. It is obvious that by merely exerting an outward pull release from the pintle 23 so as to enable the bristle holder to be replaced at will.

To secure the brush arm in position on the ferrule I5, I provide a thumb screw 30 which is threaded through the wall of the arm 22 to engage the ierrule i6 and secure the brush arm thereon. By loosening this screw, the brush arm may "ce moved endwise off of the ierrule and replaced by another arm, ii desired. I plate providing more than one arm for each body casing, giving the arms different numbers orotherwise identifying them so that for one family merely one body ii may be provided with a different arm or bristle holder for each member oi` the family. It is obvious that it is only necessary to slip the arm over the ferrule and tighten the thumb screw to assemble it for use. As the toothed end of the rack engages the pinion 2S, the latter will merely revolve into mesh with the rack, and as the arm will only go on the ferrule in proper position, due to the provision of the keyway 23a. and the protuberance 26, there is no possibility of improperly assembling the brush arm on the body. A

To start the motor I have provided a switch 3l consisting of a button 32 secured to a ilexible diaphragm 33 embedded at its periphery in the body il and sealed therein so that moisture cannot possibly gain entrance into the body through The inner end of the button is normally opened switch 35. The other contact oi this switch is that indicated by 36, both the contacts fand SG-being resiliently mounted in the body as indicated. It is obvious that by depressing the button inwardly with respect to the body, that a contact will bemade between the points on the arms 34 and 26, completing a circuit through the motor, causing the same to commence reciprocating the armature i9. As this latter is spring balanced, it will be very silent and very rapid in operation, and as it reciprocates, it will reciprocate the rack I8 and thereby oscillate the brush holder 21. As this brushing element 21 has .bristles 21a projecting from one end thereoi', a very effective and desirable brushing action will be obtained on the teeth.

From the foregoing it is obvious that I have provided a very enlcient and effective toothbrush which is electrically operated and which is pleasing in appearance, and while I have shown the preferred form-of my invention, it is to be understood that various changes may be made in its construction by those skilled in the art without departing from the,spirit of the invention as defined in the appended claims.

Having thus described my invention. what I claim and desire tol secure by Letters Patent is:

1. A device of the characterV described comprising a hollow body, a guide sleeve projecting outwardly from said body, a vibratory motor mounted in the body, a reciprocable member exi contemtending through said sleeve and guided for straight line reciprocation therein and into one end of the body, said member being operatively associated with the motor in such manner that operation of the motor will reciprocate said member, a hollow brush arm adapted to be slipped over said sleeve and the outer end oi said reciprocable member to enclose the same and be detachably secured to said sleeve, a brush element rotatably mounted on its own axis at the outer end of said arm, a pinion secured to said brush element, a rack connected with said reciprocable member in mesh with said pinion whereby reciprocation of said member will oscillate said brush element.

2. A device oi the character described comprising a. hollow body, a motor mounted in the body, a hollowzierruie'secured at its inner end in one end of the body and projecting outwardly therefrm, a reclprocable member extending through said ferrule and guided for straight line reciprocation therein, the inner end of said member being operatively associated with said motor in such manner that operation oi the latter will reciprocate said member, a hollow brush arm adapted to .be-fitted over the end of said memberand said ferrule and detachably connected with the latter, a rotatable brush element carried by the outer end of the arm, a pinion securedl to said brush element, arack secured to said reciprocable member in mesh with said pinion within the arm whereby reciprocation of said member will oscillate said brush element.

3. A device oi the character described comprising a hollow body, a guide sleeve projecting outwardly from ,said body, a j vibratory motor mounted in the body, said motor including an armature,. a reciprocable member extendingv through said sleeve and guided for straight line reciprocation therein and into one end of the body, said member being connected with the motor will reciprocate saidmember, a hollow arm enclosing the outer end of said member and detachably connected with said sleeve, a rotatable brush element mounted at the outer end of the arm, a pinion relatively fixed to said brush element, a rack connected with said member in mesh with said pinion whereby reciprocation o! the member will be accompanied by oscillation a hollow arm removably fitting over the outerend of said member and said ierrule, means for detachably connecting said arm to said Ierrule, a rotary brush element detachably secured to the outer end of the arm, a pinion relatively fixed to said elementga rackiormed as a part of said reciprocable member and in mesh with said pinion whereby reciprocation of said member will be accompanied by' oscillation of said rotatable brushing element.

TQMLINSON I. MOSELEY.

armature in such manner that operation of the Y 

